Tentering machine



June 21, 1938. E, RUSDEN TENTERING MACHINE Filed April 29, l936 2 Sheets-Sheet l INVENTOR. fizia/mflwsdxz fla/Mm ATTORNEYS.

June 21, 1938.

R. E. RUSDEN TENTERING MACHINE Filed April 29, 1936 2 Sheets-Sheet 2 I N V EN TOR. ah/0f 2? 21180? ATTORNEYS.

Patented June 21, 1938 UNITED STATES PATENT OFE'M'ZE TENTERING MACHINE Application April 29, 1936, Serial No. 76,945

9 Claims.

This invention relates to a tentering machine; and has for one of its objects the automatic tensioning of the chain so that a uniform tension of the proper amount will be appliedon this chain at all times.

Another object of the invention is the'provision of tensioning means which may be located wholly inwardly and along or above the chain rail so that the effective length of the machine is not extended.

Another object of the invention is a construction such that the tensioning means will act at substantiallythe same pressure throughout an extended. range of movement of the sprocket wheel about which the chain tov be tensioned operates.

With these and other objects in view, the invention consists of certain novel features of con struction, as will be more fully; described, and particularly pointed. out in the appended claims.

In the accompanying drawings: Fig. 1 is atop planview of the tail end of the framework forming one of the rails for guiding the tenter chain andshowing a fragmental portion of a chain positioned thereon;

Fig. 2 is a sectional view of the structure of the rail shown in Fig. 1;

Fig. 3 is a top plan view of the'rail showing with the slide member which supports the sprocket wheel removed therefrom;

Fig. 4 is a sectional view on substantially line 4-4 of Fig. 2; and

Fig. 5 is a top plan view of the slide member which fits within the opening and is guidedby the side walls thereof in the end portion of the framework forming the chain rail.

In the running of tentering machinery, the chain of clamps as it travels along the rail and about a sprocket wheel at the ends of the rail is changing in lengthsomewhat from the time that its operation commences when cold gradually until it becomes warm; and unless the operator can watch and adjust the tension this chain may be either too loose or too tight and either of these conditions will be detr-imentaLeither to the work produced by operation of themachine or to the chain itself. Furthenas the chain isr-unning, the tension within the chain changes due to me chanical reasons; and in order to=overcomethese difliculties without the use of resilient means, such as a spring or the like for compensation, I have provided a weight and transmitted thegravitational force of this weight to a slide member upon which the sprocket wheel is mounted so that constant tension may be applied thereto and compensation may be provided for within the chain itself by a lifting or lowering of the weight, while applying substantially the same force at all times; and the following is a more detailed description of the present embodiment of this invention, illustrating the preferred means by which these advantageous results may be accomplished:

With reference to the drawings, l0 designates generally the tail or foot end of a chain rail of a tentering machine resting upon its support It along which it may be adjusted by a threaded shaft 12 and a hand wheel it for varying the width between the rails of the machine. This rail consists of a frame-like structure comprising spaced bars 14 and I5 rabbeted as at l6 for supporting and guiding the links ll of a chain designated generally l8. These bars terminate in aplate-like end portion having an opening 211 and a recess 2| in line therewith. The opposite edges of thisopening 2H and recess 21 are rabbeted as at 22 forming a track and guide for the flanges 23 of a slide member 24, the body portion of which fits within the opening with its forward extension 25 extending over the recess 2i. The forward portion of this extension 25 extends upwardly as at 26 to which an abutment plate 2'! is secured by means of bolts 28, see Fig. 5. An integral stud 29 extends upwardly from this slide member 24 while the body portion in the opening is recessed as at 30 to receive a nut 3|, which threadingly engages a threaded shaft 32 supported in bearings 33 and 34 in the framework and extending through the bore 35 in the body of member 24 which is located on opposite sides of the recess 30. A bottom plate 35 is secured to the member 24 by the bolts 31 and serves to hold the threaded member 3! securely in position in the recess 3|] while extending on opposite sides of member 24 beneath the frame on either side of the opening 20. A collar adjustably held by. set screw 4| upon the shaft 32 along the unthreaded portion 42 thereof secures this collar 40 in position. A crank 43 having a handle 44 is pivoted as at 45 to the shaft 32 and may be utilized for rotating the shaft 32 to draw the member 24 outwardly along its guide 22 in the opening 20 as the collar 40 will abut against the end 46 of the frame to prevent the shaft from moving inwardly.

A sprocket wheel fill having a drum-like hub 5! is mounted upon the stud 29 through a medium of ball bearings 52 and 53. This sprocket wheel 59 engages the link I! of the chain 18 and guides the chain in its path of travel in revers ing its direction at the tail end of the rail.

Superimposed upon the framework of the rail is a saddle designated 60, the same being secured in position by bolts 6!. This saddle is provided with a pair of upstanding ears 62 between which there is pivotally supported a bell-crank lever designated 63, the same being pivoted on a pin 64 supported in both ears 62. A short arm 65 of this lever extends downwardly between the ears 62 and threadingly receives through a bore 66 a bolt 61, the head 68 of which engages the abutment plate 21, while a check nut 69 engages the arm 65 and serves to bind this bolt securely in adjusted position; A long arm ll! of the bell-crank lever 63 has a weight ll slidably mounted thereon with a set screw 12 threaded through the weight and engaging the arm l'fl to secure the weight in adjusted position along the arm.

In order to take up any slack in the chain which extends about the sprocket 50, the slide member 24 which supports the sprocket isdrawn outwardly of the rail by rotating the threaded shaft 32 by means of the handle 44, until the chain is substantially in correct position. The shaft 32 is then given a rotation in the opposite direction sufficient to back the collar Mi away from the abutment 46. The bolt 61 is then adjusted so that the long arm of the lever it is a little above the horizontal and clamped in this position by the check nut 69, while its head 68 is in engagement with the abutment plate 21. The weight is then adjusted so that the desired amount of tension will be placed upon the slide member 24 and the machine is then operated and need be given no further attention as to the tension on the chain.

In the operation of the machine equipped with this automatic tension means the weight moves up and down asthe chain operates, thus compensating for all sorts of different tensions which may exist in the chain momentarily at any certain time. Further, as the chain heats up and elongates the slide moves to take up the amount of elongation and maintains constant tension at all times, which is not possible with a spring as an elongation will lessen the tension and a co1npression increase the tension due to movement of the slide. Further, adjustment to compensate for the changes which occur is not practical during the operation of the chain about its rail.

The foregoing description is directed solely towards the construction illustrated, but I desire it to be understood that I reserve the privilege of resorting to all the mechanical changes to which the device is susceptible, the invention being defined and limited only by the terms of the appended claims.

I claim:

1. In a tentering machine, an endless chain, a sprocket wheel about which the chain travels disposing the same in parallel lengths, a member carrying a stud upon which said wheel is rotatably mounted, means for slidably mounting said member, means for exerting a substantially invariable constant pressure on said member regardless of its position along its support comprising a lever located between the lengths of chain, a weight on one arm thereof, and means carried by another arm for transmitting pressure to said member.

2. In a tentering machine, an endless chain, a sprocket wheel about which the chain travels, a member carrying a stud upon which said wheel is rotatably mounted, means for slidably mounting said member, means for exerting a. substantially invariable constant pressure on said member regardless of its position along its slidable support, comprising a bell-crank lever, a weight on one arm of the lever, and an adjustable member carried by the other arm of said lever and engaging said stud carrying member to exert pressure thereon.

3. In a tentering machine, a framework forming a chain rail, a member slidably mounted therein at one end portion thereof, a stud carried by said member, a sprocket wheel rotatably mounted on said stud, an endless chain having a bight extending about said wheel with adjacent portions disposed in parallel lengths, a saddle secured to said framework inwardly of the rail from the Wheel and between the lengths of chain, a lever pivoted on said saddle and engaging said member, and loading means on said lever tending to move the same about its pivot to exert a substantially invariable pressure on said member.

4. In a tentering machine, a framework forming a chain rail, a member slidably mounted therein at one end portion thereof, a stud carried by said member, a sprocket wheel rotatably mounted on said stud, an endless chain having a bight extending about said wheel, a saddle secured to said framework inwardly of the rail from the wheel, a bell-crank lever pivoted on said saddle and provided with a threaded stud engaging said member, and loading means on said lever tending to move the same about its pivot and exert pressure on said member.

5. In a tentering machine, an endless chain, a sprocket wheel about which the chain travels disposing the same in parallel lengths, a member carrying a stud upon which said wheel is rotatably mounted, means for slidably mounting said member, means arranged for exerting a substantially unvariable constant pressure on said member substantially central and mid-way between said parallel chain lengths, said means comprising a gravity-operated member located between the lengths of chains, and means for transmitting the pressure thereof to said stud carrying member.

6. In a tentering machine, a chain rail, an endless chain, a sprocket wheel at one end portion of said chain rail about which the chain travels, a member carrying a stud upon which said wheel is rotatably mounted, means for slidably mounting said member, means for exerting a constant pressure on said member comprising a member pivotally mounted adjacent said slidable member and between the stretches of said chain, said pivoted member having an arm extending away from said slidable member, means carried by said arm for urging said member about its pivot, and means operable by said arm for transmitting the pressure to said stud carrying member in a direction opposite to that in which the arm extends.

7. In a tentering machine, a framework form ing a chain rail, a member slidably mounted therein at one end portion thereof, a stud carried by said member, a sprocket wheel rotatably mounted on said stud, an endless chain having a bight extending about said wheel with adjacent portions disposed in parallel lengths, a saddle secured to said framework inwardly of the rail and adjacent to the wheel and between the lengths of chain, a pressure exerting member pivotally mounted on said saddle and having an arm extending from its pivot towards the opposite end portion of said chain rail, means carried by said arm for urging said pivoted member about its pivot, and means operable by said arm for transmitting the pressure to said slidable member in a direction opposite to that in which the arm extends.

8. In a tentering machine, an endless chain, a sprocket Wheel about which the chain travels, a member carrying a stud upon which said wheel is rotatably mounted, means for slidably mounting said member, means for exerting a constant pressure on said member, comprising a bell crank lever, a weight on one arm of the lever, an adjustable member carried by the other arm of said lever and engaging said stud carrying memher to exert pressure thereon, and means for locking said adjustable member in adjusted position.

. 9. The combination with a movable support on which a member is rotatabiy mounted and over which rotatable member an endless member is trained, of a bell crank, a weight on one arm of the lever, and an adjustable member carried by the other arm of said lever and operatively con nected with said movable support for exerting pressure thereon for urging said support and rotatable member in one direction.

RICHARD E. RUSDEN. 

